Staurosporine blocked normal cells at G1/S boundary
Abstract
AIM: To reveal the regulating difference of G1/S-phase transition between normal
and tumor cells by using staurosporine, an unspecific kinase inhibitor.
METHODS: Flow cytometry, Dot blot, kinase activity assay, and electrophoresis.
RESULTS: A 18-h treatment with staurosporine (5 micrograms.L-1) blocked normal
cell line 2BS cells (normal human embryonic lung fibroblast, 5-20 passages) in G1
phase, decreased their thymidine kinase (TK) mRNA level and activity, and also
dephosphorylated an intracellular 107 kDa protein. Meanwhile, all these effects
in 2BS cells disappeared only by washing staurosporine away. Such kind of effects
did not occur in tumor cell line BGC-823 cells (human stomach cancer cell).
CONCLUSION: During the period of G1/S-phase transition, the kinases involved are
more sensitive to staurosporine in normal cells than in tumor cells.
Keywords:
and tumor cells by using staurosporine, an unspecific kinase inhibitor.
METHODS: Flow cytometry, Dot blot, kinase activity assay, and electrophoresis.
RESULTS: A 18-h treatment with staurosporine (5 micrograms.L-1) blocked normal
cell line 2BS cells (normal human embryonic lung fibroblast, 5-20 passages) in G1
phase, decreased their thymidine kinase (TK) mRNA level and activity, and also
dephosphorylated an intracellular 107 kDa protein. Meanwhile, all these effects
in 2BS cells disappeared only by washing staurosporine away. Such kind of effects
did not occur in tumor cell line BGC-823 cells (human stomach cancer cell).
CONCLUSION: During the period of G1/S-phase transition, the kinases involved are
more sensitive to staurosporine in normal cells than in tumor cells.